1. Field of the Invention
The invention relates to coating devices and in particular to an apparatus for holding a spreading device, such as a doctor blade or rod, utilized to regulate the coating thickness in the coating of a web of material.
2. Description of Related Technology
An apparatus for regulating the coating thickness in the coating of a web of material is disclosed in DE 28 51 014 (corresponding to Wohlfeil, U.S. Pat. No. 4,282,826 (Aug. 11, 1981)). Such a device includes a clamping mechanism for holding a flexible mounting member, a doctor rod support bed attached to the mounting member, and a doctor rod mounted in the doctor rod support. A thrust bar exerts pressure on a pressing tube which in turn presses against the doctor rod support, pressing the doctor rod onto a web of material wrapped onto a counter roll of a coating machine.
In the device disclosed in DE 28 51 014, the pressing tube is mounted on the doctor rod support bed. Thus, if the doctor rod and the doctor rod support bed are replaced with a coating blade, the thrust bar would become a profile strip (i.e. comb strip) and would press against the coating blade, retaining all the coating profiling possibilities. However, in the device disclosed in DE 28 51 014, it is necessary that the doctor rod bed support be supported in a sliding guide of the mounting member. Such a configuration typically requires the use of more expensive materials and is relatively expensive to manufacture. With respect to other spreading devices known in the art, the replacement of a doctor rod with a coating blade often requires extensive rebuilding of the device.